Suspended animation

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Suspended animation is the slowing of life processes by external means without termination. Breathing, heartbeat, and other involuntary functions may still occur, but they can only be detected by artificial means. Extreme cold can be used to precipitate the slowing of an individual's functions; use of this process has led to the developing science of cryonics. Cryonics is another method of life preservation but it freezes organisms using liquid nitrogen that will preserve the organism "dead" until reanimation. Outside of science fiction, the technique has almost never been applied to humans for more than a few hours.[citation needed] The case of Laina Beasley is an exception; she was kept in suspended animation as a two-celled embryo for 13 years.[1][2]

Placing astronauts in suspended animation has been proposed as one way for an individual to reach the end of an interplanetary or interstellar journey, avoiding the necessity for a gigantic generation ship; occasionally the two concepts have been combined, with generations of "caretakers" supervising a large population of frozen passengers.

Since the 1970s, hypothermia has been induced for some open-heart surgeries as an alternative to heart-lung machines. Hypothermia, however, only provides a limited amount of time in which to operate and there is a risk of tissue and brain damage for prolonged periods.[citation needed]

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[edit] Experiments

[edit] Temperature-induced

In June 2005 scientists at the University of Pittsburgh's Safar Center for Resuscitation Research announced they had managed to bring dogs back to life, most of them without brain damage, by draining the blood out of the dogs' bodies and injecting a low temperature solution into their circulatory systems, which in turn keeps the bodies alive in stasis. After 3 hours of being clinically dead, their blood was returned to their circulatory systems, and the dogs were revived by delivering an electric shock to their hearts. The heart started pumping the blood around the frozen body, and the dogs were brought back to life. Scientists hope to begin human testing and have already begun discussions with hospitals to use "suspended animation" if everything else fails.

While most of the dogs were fine, a few of the revived dogs had severe nervous and movement coordination damage, causing them to be mentally disabled, and demonstrating behavior that was deemed "zombie" like. This has been pushed further by the media which named them "zombie dogs".[3] There is concern that this technique, if used on humans could result in brain damage similar to those suffered by some of the dogs in the experiment. In extreme cases, doctors can now use induced hypothermia which reduces brain and heart activity to a minimum. This allows doctors to have more time to heal or diagnose a patient.

On January 20, 2006, doctors from the Massachusetts General Hospital in Boston announced they had placed pigs in suspended animation by a similar technique. The pigs were anaesthetised and a major blood loss was induced. After they lost about half their blood the remaining blood was replaced with a chilled saline solution. As the body temperature reached 10 °C the damaged blood vessel was repaired and the blood was returned. The method was tested 200 times with a 90 percent success rate.[4]

[edit] Chemically-induced

An article in the April 22, 2005. issue of the scientific journal Science reports success towards inducing suspended animation-like hypothermia in mice. The findings are significant, as mice do not hibernate in nature. The laboratory of Mark B. Roth [[1]] at the Fred Hutchinson Cancer Research Center [[2]] in Seattle, Washington, placed the mice in a chamber containing 80 ppm hydrogen sulfide for a duration of 6 hours. The mice's core body temperature dropped to 13 degrees Celsius and metabolism, as assayed by carbon dioxide production and oxygen use, decreased 10-fold.

On October 9, 2006, the Massachusetts General Hospital in Boston announced they had been able to hibernate mice using the same method. Their heart rate was slowed down from 500 to 200 beats per minute, respiration fell from 120 to 25 breaths per minute and body temperature dropped to 30 °C (natural: 39 °C). After 2 hours of breathing air without hydrogen sulfide the mice returned to normal. Further studies are needed to see if the gas had poisonous effects on the brain.[5]

Experiments on sheep[6] and partially pigs[7] have been unsuccessful, suggesting that application to large mammals may not be feasible.

[edit] Human hibernation

There are many research projects currently investigating how to achieve "induced hibernation" in humans.[8][9] This ability to hibernate humans would be useful for a number of reasons, such as saving the lives of seriously ill or injured people by temporarily putting them in a state of hibernation until treatment can be given. NASA is also interested in possibly putting astronauts in hibernation when going on very long space journeys, making it possible, one day, to visit far-away places.

There are cases of accidental human hibernation. The most recent is the case of Mitsutaka Uchikoshi, a Japanese man who survived the cold for 24 days in 2006 without food or water when he fell into a hypothermic state similar to hibernation.[10]

[edit] In fiction

Suspended animation is a common trope in fiction, particularly in Science Fiction.

  • In Futurama, the character Philip J. Fry was frozen for a 1000 years and was awaken on New Year's Eve of the year 2999. In the episode The Why of Fry, the Nibblonians set Fry to stop the Brainspawn from destroying the universe. Whilst he did stop them from doing so, he was unable to escape, and the brain's reveal that Nibbler froze Fry and he tells Fry that he was the one chosen to stop the brains because of his genetic disorder which he acquired after becoming his own grandfather (Seen in Roswell That Ends Well)
  • Another common use is in space voyages, where the crew is put in hyper-sleep while the ship travels to its destination, saving food and water as well as the crew's lifespans, as in The Twilight Zone episode "The Long Morrow", the films 2001: A Space Odyssey, Alien, and Planet of the Apes and RocketMan, as well as in Buzz's mind in Toy Story. In the Inquisitor War series of novels set in the Warhammer 40,000 universe characters are kept in suspended animation in a stasis chest designed for the long-term storage of food. Their last thoughts as they are suspended remain with them for the entire duration, being either a torture, maddening or a blessing depending on the thought.
  • Many of the deities of the Cthulhu Mythos, such as the titular Cthulhu himself, are known to be in long impermanent deaths or sleeps which correspond with the modern idea of suspended animation. Equally gazing upon the Great Old One Ghatanothoa is so hideous that anyone who gazes upon it (or even a perfect replica) is petrified into a living mummy. The victim is permanently immobilized—the body taking on the consistency of leather and the internal organs and brain preserved indefinitely—yet remains fully aware.
  • Suspended animation has also been used in many stories (such as the film Demolition Man and the Tekwar novels) as an alternative method of containing incarcerated criminals. The rationale behind this being that prisoners under suspended animation consume less resources (such as food, water, housing and medical care) and that the only significant expense is the maintenance of the suspension units and the security around them. Similarly, In Red Dwarf, the premise of the show is that the main character, Dave Lister has been put into suspended animation until he is returned to earth for punishment. However, the crew of the ship is killed by radiation, and he is revived millions of years later when the radiation subsides. And in a famous example from Star Wars, character Han Solo is put into suspended animation by being frozen into a block of carbonite. Detractors[who?] have noted that because no aging takes place in suspended animation, life sentences are pointless. Also, because suspended animation removes all sense of time passing for the prisoner, it undermines the punishing effect of prison life.
  • In an early literary reference, from Romeo and Juliet, Juliet takes a potion cooked up by a priest that places her in a death-like state. She uses it to escape her family so that she can marry her love, Romeo. Unfortunately, Romeo too is fooled and commits suicide in sorrow at her "death."
  • In Smallville, suspended animation is referenced as Kara Kent is kept in a frozen state for 18 years, along with her ship. Clark Kent refers to this as suspended animation while talking to her.
  • In Fringe, in the start of each Fringe Episode, the second title page shows Suspended Animation.
  • In the Sonic the Hedgehog (series) series, a hedgehog named .Shadow the Hedgehog was believed to have been put into suspended animation 50 years ago for the means of keeping him alive but locked up, as the government believed he was too strong.

[edit] References

  1. ^ "Longest frozen embryo baby born". BBC News. 2005-07-06. http://news.bbc.co.uk/2/hi/health/4655035.stm. Retrieved on 2009-01-14. 
  2. ^ "Triplets born 13 years apart". Times Online. 2005-07-06. http://www.timesonline.co.uk/tol/news/world/us_and_americas/article540837.ece. Retrieved on 2009-01-15. 
  3. ^ Jennifer Bails (2005-06-29). "Pitt scientists resurrect hope of cheating death". Pittsburgh Tribune-Review. http://www.pittsburghlive.com/x/tribune-review/trib/regionals/s_348517.html. Retrieved on 2006-10-10. 
  4. ^ "Doctors claim suspended animation success". The Sidney Morning Herald. 2006-01-20. http://www.smh.com.au/articles/2006/01/20/1137553739997.html. Retrieved on 2006-10-10. 
  5. ^ "Gas induces 'suspended animation'". BBC News. 2006-10-09. http://news.bbc.co.uk/2/hi/health/5412824.stm. Retrieved on 2006-10-10. 
  6. ^ Haouzi P, Notet V, Chenuel B, Chalon B, Sponne I, Ogier V, Bihain B (2008). "H2S induced hypometabolism in mice is missing in sedated sheep". Repiratory Physiology &Amp; Neurobiology 160 (1): 109–115. doi:10.1016/j.resp.2007.09.001. PMID 17980679. 
  7. ^ Li, Jia; Zhang, Gencheng; Cai, Sally; Redington, Andrew N (January 2008). "Effect of inhaled hydrogen sulfide on metabolic responses in anesthetized, paralyzed, and mechanically ventilated piglets" (Subscription required). Pediatric Critical Care Medicine 9 (1): 110–112. doi:10.1097/01.PCC.0000298639.08519.0C. http://www.pccmjournal.com/pt/re/pccm/abstract.00130478-200801000-00021.htm. Retrieved on 2008-03-23. "H2S does not appear to have hypometabolic effects in ambiently cooled large mammals and conversely appears to act as a hemodynamic and metabolic stimulant.". 
  8. ^ New Hibernation Technique Might Work on Humans | LiveScience at www.livescience.com
  9. ^ Race to be first to ‘hibernate’ human beings - Times Online at www.timesonline.co.uk
  10. ^ Japanese man in mystery survival at BBC News

[edit] See also

[edit] External links

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